The invention relates more particularly to video compression adapted to archiving.
The compression constraints of a video document are less significant when concerned with archiving the video than when concerned with compressing the video for transmission.
Specifically, a video intended to be compressed, transmitted and decompressed in real time must be compressed by taking the images one after another, in a chronological order, as done by coding methods such as MPEG-2 for example.
When the images are intended to be recorded on storage media for long term storage, such as hard disks for example, it is possible to compress them in any order so as to optimize the quantity of information stored and thus to minimize the storage resources required. The compression constraints are therefore not the same as in the case of real time coding/decoding.
The invention therefore relates to the ordering of the images of a video document prior to coding so as to increase the degree of compression. Actually, several methods of data compression use groupings into clusters. However, once the clusters have been finalized, the coding is performed directly on the images in their chronological order.
The present invention makes it possible to circumvent this chronological order and to code the images while obtaining an optimized degree of compression.